Portable aircraft maintenance platform

ABSTRACT

A maintenance platform ( 10 ) comprises a main frame ( 12 ) with base frames ( 12,14 ) releasably interconnected by split clamps ( 50 ) and load transfer couplers ( 52 ). Upper extension frames ( 62,64 ) are mounted on the base frames ( 12,14 ). A balcony ( 82 ) and stabilizers ( 100 ) are also provided. The platform ( 10 ) is of modular construction and can be assembled and disassembled manually without tools for use on either improved or unimproved surfaces.

TECHNICAL FIELD

[0001] The present invention relates generally to scaffolds and workplatforms. More particularly, this invention relates to a new and uniqueaircraft maintenance platform of modular construction for knockdown andportability.

BACKGROUND ART

[0002] A variety of scaffolds have been available heretofore. Suchscaffolds generally include rigid frames that can be stacked andinterconnected together to form an elevated work platform of the desiredheight, such as for working on walls, ceilings, chimneys or windows of abuilding, for example. Such scaffolds are generally transported by truckin pieces to the work site for assembly. When assembled, they aregenerally free-standing, but tend to be rather heavy for adequatestrength, rigidity and stability. Such scaffolds usually have adjustablefeet for leveling purposes, and may have lockable casters to facilitatelocation and relocation as desired.

[0003] While the scaffolds of the prior art generally provide elevatedwork platforms, they do not accommodate much lateral extension duringuse. They become more top heavy with height and particularly withworkers on them in use. The scaffolds of the prior art can becomeunstable and even tip over if a worker leans out too far. Sometimes theycan be temporarily attached to the adjacent structure for safety, suchas in a building construction project, but are most often used to accessareas directly overhead or immediately next to the scaffold.

[0004] Various specialized scaffolds have also been availableheretofore. For example, U.S. Pat. No. 4,592,447 shows a movablepedestal scaffold. U.S. Pat. No. 4,194,591 shows a mobile scaffold withfixed-use-position outriggers. U.S. Pat. No. 4,155,424 shows a mobilescaffold with a main frame and pivotal outer frames so that it can berolled through narrows doors or aisles. U.S. Pat. Nos. 3,454,131,2,665,950 and 2,438,173 also show scaffolds representative of the priorart.

[0005] Aircraft maintenance requires the use of specialized scaffolds inorder to access areas that cannot otherwise be reached. For example,there may be certain access doors or other areas that cannot be reachedwithout specialized scaffolding due to the aircraft's configuration.Little or no maintenance work can or should be done while standing onthe aircraft itself. The scaffolding cannot be temporarily attached tothe aircraft as is typical in building construction. As a result, suchspecialized scaffolds or work platforms must be free-standing, and thustend to be rather cumbersome and heavy in order to achieve the stabilitynecessary for working in an elevated position over part of the aircraft.Further, different scaffolds or work platforms are usually required formaintaining different types of aircraft, particularly with helicoptersand fixed wing aircraft, whose configurations are quite different.

[0006] Such scaffolds or work platforms have not been adapted for use ondifferent aircraft types as needed, and are not readily transportable.They have thus tended to be limited for use in hangars where they arestored. This in turn means that the aircraft must be flown to a facilitywhere the hangar is located for all but the most basic maintenance,resulting in unnecessary downtime and expense. Such logistics problemsare severe in military applications due to the variety of aircraft typesin service, and the fact that some aircraft, such as helicopters,typically operate in the field. This has been compounded by the factthat aircraft systems today are more complex and require more frequentmaintenance for readiness.

[0007] Heretofore there has not been available a portable aircraftmaintenance platform that is readily adapted for use on differentaircraft types, either on a prepared surface such as in a hangar or onan unimproved surface, such as in the field at a forward base as inmilitary applications.

[0008] A need has thus arisen for a portable aircraft maintenanceplatform that is readily adapted for use on different aircraft types,either on a prepared surface such as in a hangar, or on an unimprovedsurface, such as in the field, and which is of modular construction forknockdown and portability so that more maintenance can be done in thefield at the point of need.

SUMMARY OF INVENTION

[0009] The present invention comprises a portable aircraft maintenanceplatform that overcomes the foregoing and other difficulties associatedwith the prior art. In accordance with the invention, there is providedan aircraft maintenance platform of lightweight, modular construction sothat it can be assembled, disassembled, and packaged for air, vehicle ormanportability by one or two persons. The maintenance platform hereinincludes a basic main frame to which other modules can be added asdesired to enhance overall versatility and function. The main frameincludes two lower sections and two upper extensions interconnected byvarious braces, couplers and clips. An adjustable balcony and a lowerstabilizer can be mounted on one side of the main frame, if desired,depending upon the type of aircraft to be maintained. The modules areinterconnected by various releasable connectors, all of which can bedone manually without tools, so that the platform can be configured asdesired and yet still be capable of knockdown and repacking fortransport to another site as needed. The present invention isparticularly adapted for use in commercial and military applicationsconducted in remote or unimproved locations where packaging fortransportation is critical, and is capable of rapid assembly intomulti-functional structural combinations to suite site-specific andconfiguration-specific needs meeting aircraft and vehicle requirements.

BRIEF DESCRIPTION OF DRAWING

[0010] A better understanding of the invention can be had by referenceto the following Detailed Description in conjunction with theaccompanying Drawing, wherein:

[0011]FIG. 1 is an illustration of the portable aircraft maintenanceplatform of the invention, one positioned in front of and anotherpositioned next to a helicopter;

[0012]FIG. 2 is a perspective view of the portable aircraft maintenanceplatform and balcony module herein;

[0013]FIG. 3 is a side elevational view of the portable aircraftmaintenance platform and balcony module herein;

[0014]FIG. 4 is a partially exploded perspective view of the portableaircraft maintenance platform and balcony module herein;

[0015]FIG. 5 is a fully exploded perspective view of the portableaircraft maintenance platform herein;

[0016]FIG. 6 is an exploded, detail view of an adjustable leg;

[0017]FIG. 7 is an enlarged side view of one end of a brace connected toa frame section;

[0018]FIG. 8 is an enlarged side view of one end of a walkway connectedto a frame section;

[0019]FIG. 9 is an exploded perspective view of a frame clamp;

[0020]FIG. 10 is an exploded perspective view of a load transfercoupler;

[0021]FIG. 11 is an exploded perspective view of the connection betweenthe upper and lower base frames;

[0022]FIG. 12 is a partial perspective view of the inner balcony frame;

[0023]FIG. 13 is a partial perspective view of the outer balcony frame;

[0024]FIGS. 14 and 15 are exploded perspective views of the stabilizer;

[0025]FIG. 16 is an perspective view showing an alternate clamp;

[0026]FIG. 17 is a perspective view of the portable aircraft maintenanceplatform herein with outriggers;

[0027]FIG. 18 is an illustration of the portable aircraft maintenanceplatform herein disassembled and ready for packing in cases as a kit fortransportation; and

[0028]FIG. 19 is a perspective view, partially cutaway, showing detailsof the large transport case for then platform.

DETAILED DESCRIPTION

[0029] Referring now to the Drawing, wherein like reference numeralsdesignate like or corresponding elements throughout the views, andparticularly referring to FIG. 1, there is shown a portable aircraftmaintenance platform 10 incorporating the invention. The platform 10 isof modular construction, and is adapted primarily for use with aircraft,such as a helicopter as shown, but can also be used with fixed wingaircraft or other types of vehicles. As will be explained more fullyhereinafter, the platform 10 can be arranged in various configurationsfor maximum versatility, while also being adapted for portability andmanual assembly/disassembly without tools.

[0030] Referring primarily to FIGS. 1-6, the platform 10 includes a mainframe 12 comprising two base frames 14 and 16 which are clamped togetherto form a rigid assembly. The main frame 12 is preferably comprisedprimarily of lightweight tubing, such as 6062T6aircraft grade aluminumof about two inch diameter and 0.025 in wall thickness, although anysuitable material could be used.

[0031] Each rigid base frame 14 and 16 includes two ladder-like ends 18,each of which includes two laterally spaced uprights 20 interconnectedby vertically spaced-apart rungs 22. As shown five rungs 22 areprovided, although any suitable number could be used. In the preferredembodiment, each end 18 is about 26 inches wide and about 78 inchestall. A gusset or flat crosspiece 24 is preferably provided beneath theupper rung 22 for carrying assembly instructions.

[0032] Vertically adjustable legs 26 are provided in the lower ends ofuprights 20 for leveling attachment, to which are attached lockableswivel casters 28 for use on a hard surface. Swivel platforms 30 can besubstituted for casters 28 if platform 10 is to be used in the field onan unimproved surface.

[0033] The ladder-like frame ends 18 are interconnected by diagonal andhorizontal cross braces 32 and 34 coupled between rungs 22. In thepreferred embodiment, the ends are spaced apart about 98 inches. Theends of each brace 32,34 are curved with spring clips 36 therein so asto positively snap onto the adjacent rung 22, as best seen in FIG. 7.

[0034] Base frame 14 also includes a walkway 38 connected between therungs 22. Walkway 38 preferably includes a wooden surface 42 secured tothe tops of rails 42, the ends of which are notched to fit over rungs22, as best seen in FIG. 8. In the preferred embodiment, slidablekeepers 44 are also provided in the notched ends of rails 42 forpositive, releasable attachment to rungs 22. The walkway 38 can thus beconnected between any two opposite rungs 22 at the desired height.

[0035] Walkway 38 preferably includes a hinged access door 46, with aladder 48 also preferably being provided for facilitating movement ofpersonnel between the upper and lower walkways in platform 10. The upperends of ladder 48 are preferably configured like the ends of braces 32and 34 for releasable snap engagement with a rung 22 on one of the ends18.

[0036] The base frames 14 and 16 are releasably secured together at eachend by clamps 50 and load transfer couplers 52, the details of which areshown in FIGS. 9 and 10. In the preferred embodiment, two clamps 50 andone coupler 52 are used on each end of subframes 14 and 16. Each splitclamp 50 includes mating halves 50 a and 50 b secured together overopposite sides of the adjacent uprights 20 of the subframes by bolts 54and wing nuts 56 extending therebetween, as best seen in FIG. 9. Theinside surfaces of split clamps 50 are configured for snug receipt ofthe uprights 20 therein, in parallel arrangement.

[0037] Each split load transfer coupler 52 includes mating halves 52 aand 52 b secured together over opposite sides of the adjacent uprights20, as well as opposite rungs 22 of subframes 14 and 16 by bolts 58 andwingnuts 60, as best seen in FIG. 10. The inside surfaces of splitcouplers 50 are configured for snug receipt of the uprights 20 and theirrespective rung 22 therein, in perpendicular arrangement.

[0038] The use of inline clamps 50 and crisscross load transfer couplers52 provides for proper load transfer and distribution between baseframes 14 and 16 within main frame 12. This comprises a significantfeature of the invention.

[0039] Upper frames 62 and 64 are mounted on the base frames 14 and 16,respectively for vertical extension as desired. Again, each upper frame62, 64 includes two ladder-like ends 66, each having two laterallyspaced uprights 68 interconnected by vertically spaced-apart rungs 70.As shown four rungs 70 are provided, although any suitable number couldbe used. In the preferred embodiment, each frame 62, 64 is about 26inches wide and about 65 inches tall. Again, the ends 66 areinterconnected by diagonal and horizontal cross braces 32 and 34 coupledbetween rungs 70 as desired to serve as guard rails. Again, clamps 50are used to secure the upper frames together, two of which arepreferably used on each end.

[0040] The upper ends of base frames 14,16 and the lower ends of upperframes 62,64 are adapted for telescoping, releasable locked engagement,as best seen in FIG. 11. In particular, the reduced lower ends ofuprights 68 fit into the upper ends of uprights 20, to be interlocked byclips 72 extending through aligned holes 74 and 76 therein. As shown,each interlock clip 72 includes a collar 72 a with an pin 72 b therein.A second hole 78 is preferably provided below each hole 76 for storingclips 72 in unlocked position when not in use.

[0041] It will thus be appreciated that platform 10 can be assembledwith or without the upper frames 62,64 as desired when more workingheight is needed. The braces 32,34 can be positioned as desired, as canthe walkways 38 and ladder 48. The walkways 38 in upper frames 62 and 54can be positioned at the same or different levels. If positioned at thesame level, an extension 80 of generally T-shaped cross-section can beused to close the gap therebetween for better safety.

[0042] In the preferred embodiment, the upper ends of uprights 68 ineach end 66 similarly include locking clips 72 and holes 74,76 so thatadditional upper frames 62,64 can be added, if desired. Additionalclamps 50 and load transfer couplers 52 can also be used for additionalrigidity.

[0043] Referring to FIGS. 2-5 in conjunction with FIG. 12, platform 10preferably includes an adjustable balcony 82 for added versatility andlateral extension as desired. Balcony 82 is mounted on one side ofmainframe 12, and includes inner frame 84 and outer frame 86. Innerframe 84 includes two rigid ladder-like ends 88, each of which includestwo laterally spaced uprights 90 interconnected at their upper ends byvertically spaced-apart rungs 92, with a brace 93 secured between thelower rung and the relatively longer inner upright, as best seen in FIG.12. As shown five, rungs 92 are provided, although any suitable numbercould be used. In the preferred embodiment, each end 88 is about 26inches wide and about 100 inches tall overall.

[0044] The ends 88 of inner balcony frame 84 are each similarlyconnected to frames 16 and 64 by split clamps 50 and load transfercouplers 52, as shown. Two clamps 50 and one coupler 52 are preferablyused on each inner balcony frame 84, although any suitable number couldbe used. In the preferred embodiment, one mating half 52 b of each clamp50 is welded or otherwise secured to the inner upright 90 in the desiredposition to facilitate assembly. The ends 88 are also interconnected byat least one horizontal brace 34, with a walkway 38 being connectedbetween rungs 92 as desired.

[0045] Referring to FIGS. 2-5 in conjunction with FIG. 13, the outerbalcony frame 86 similarly includes two rigid ladder-like ends 94, eachof which includes two laterally spaced uprights 96 interconnected byvertically spaced-apart rungs 98 The outer balcony frame 86 isrelatively narrower and shorter than the inner balcony frame 84. Asshown four rungs 98 are provided, although any suitable number could beused. In the preferred embodiment, each end 94 is about 11 inches wideand about 46 inches tall.

[0046] Similarly, the ends 94 of outer balcony frame 86 are connected tothe respective inner balcony frames 84 by split clamp 50 and couplers52, as best seen in FIG. 13. Again, half of the clamp 50 is preferablywelded or otherwise secured to the inner upright 96 in the desiredposition to facilitate assembly. The ends 94 are also interconnected byat least one horizontal brace 34, with a walkway 38 being connectedbetween rungs 92 as desired, to provide a step. Since the outer balconyframe 88 is relatively narrower than the inner frame 84, the walkway 38is connected and supported between rungs 92 and 98.

[0047] If the outer balcony frame 86 is not needed, then it can beomitted from balcony 82, along with the second walkway 38, in which casethe brace 34 would be connected between ends 88.

[0048] Referring to FIGS. 14 and 15, when using balcony 82, oradditional upper extension frames 62 and 64, a stabilizer 100 is alsoprovided, which should be connected to the base frames 14 and 16beforehand. The stabilizer 100 similarly includes two relatively long,but narrow ladder-like ends 102, each preferably including twovertically spaced-apart rungs 104 interconnected by five laterallyspaced-apart uprights 106, although any suitable number could be used.In the preferred embodiment, each end 94 is about 104 inches long andabout 4.5 inches tall. The inner balcony ends 102 are each preferablyconnected to frames 14 and 16 by two clamps 50, although any suitablenumber could be used. Adjustable legs 26 and swivel platforms 30 areprovided at the outer ends 102 for leveling, with another cross brace 32connected therebetween.

[0049] Referring to FIG. 16, there is shown an alternate clamp 110 whichcan be used instead of clamps 50 and couplers 52 to secure balcony 82 tothe mainframe 12. Clamp 110 includes mating halves 110 a and 110 bconnected at one side by a hinge 112. Each clamp half 110 a is secureddirectly to the inner uprights 92. such as by welding, to facilitateassembly. The pivotal clamp half 110 b is secured by means of a bolt114, one end of which is pivoted to the other side of clamp half 110 aand the outer threaded end of which is fits into a notch on the pivotalhalf 110 b and is tightened by a wingnut 116.

[0050] Referring again to FIG. 17, corner outriggers 118 may used 10under some conditions for additional stability, such when upperextension frames 62,64 are installed or when platform 10 is used in thefield on a soft unimproved surface. Each outrigger 118 comprises a leg120, the upper end of which is coupled to an upright of the respectiveend frame 18 similar to braces 32 and 34, with a pivotal foot 122 beingprovided on the lower end. A brace 124 is also similarly connectedbetween each leg 120 and the respective upright 20, the inner end ofwhich is preferably pivoted to the leg at 126 so that the outrigger 118can be folded together when stowed and not in use.

[0051]FIGS. 18 and 19 show the aircraft maintenance platform 10 inknocked-down condition ready for transportation in collapsible bags orcases 130, 132 and 134. Cases 130, 132 and 134 are preferablyconstructed of woven plastic, such as cordura nylon, for durability andlight weight, although canvas or any suitable material could be used.The relatively smaller cases 130 and 132, which are of the same size,are adapted to carry the smaller components of platform 10, such theclamps 50, couplers 52, etc. In the preferred embodiment, cases 130 and132 are each about 18 inches long by 18 inches wide by 6 inches deep,closable about three sides by a zipper 136 with a carrying handle 138sewn to the top as shown. The cases 130 and 132 are dimensioned to fitbetween the rungs of the main frame 12 when packed into case 134, whichis adapted to carry the larger/longer components of platform 10.

[0052] The details of the larger case 134 are best seen in FIG. 19. Inthe preferred embodiment, case 134 is about 110 inches long by 30 incheswide by 16 inches deep, closable about three sides by a zipper 140 withcarrying handles 142 sewn to the sides and ends as shown. Internalinserts 144 are provided in the ends for puncture resistance. Theinserts 144 can be formed of wood or other suitable material. Case 134includes two longitudinal straps 146, which are preferably sewn alongsubstantially the entire length of the case, the ends of which aresecured by double D-rings near the zipper 140 as shown. Similarly, case134 also includes two circumferential straps 148, which are preferablysewn about substantially the entire girth of the case, the ends of whichare also secured by double D-rings near the zipper 140 as shown. Straps142 and 144 can be formed from nylon webbing or other suitable material.A nameplate 150 and clear window inserts 152 are provided on the top ofcase 134 for identification and documentation as desired. Metal feet 154are preferably riveted to the bottom of case 134 near the corners fordurability.

[0053] From the foregoing, it will be appreciated that the presentinvention comprises a portable aircraft maintenance platform havingseveral advantages over the prior art. The platform herein is of modularconstruction for ease of assembly, disassembly and transportation. Theplatform herein incorporates several common and/or interchangeablecomponents to simplify assembly/disassembly quickly by hand withouttools, in a variety of configurations depending on the particularaircraft or vehicle to be maintained. When disassembled, the platformherein can be readily stowed in compact shipping cases as a kit forportability. The platform herein can be configured or reconfigured asdesired, for use on either improved or unimproved surfaces in the field.Other advantages will be evident to those skilled in the art.

[0054] Although particular embodiments of the invention have beenillustrated in the accompanying Drawing and described in the foregoingDetailed Description, it will be understood that the invention is notlimited only to the embodiments disclosed, but is intended to embraceany equivalents, modifications and/or rearrangements of elements fallingwithin the scope of the invention as defined by the following Claims.

What is claimed is:
 1. A modular maintenance platform, comprising: apair of rigid base frames, each base frame including a pair of opposingends; the ends of each base frame including laterally spaced-apartuprights secured together by a plurality of vertically spaced-apartrungs, each upright having upper and lower ends; means for releasablyinterconnecting the opposing ends of each base frame in predeterminedlongitudinally spaced-apart relationship; means connected to the lowerends each upright for adjustably supporting the scaffold; at least onewalkway releasably secured between the rungs of the opposing uprightsthereof; and clamp means for releasably securing said base frames inside-by-side relationship